A method for forming a microfluidic channel with improved flow characteristics for one or more analytes is disclosed. A microfluidic channel having modified surfaces is formed in fused silica. The fused silica surfaces are modified by the addition of a layer of borophosphosilicate glass. The addition of the borophosphosilicate glass results in an improved flow velocity profile of the analyte. As a result, control over the position and movement of analytes within the solution is improved.